A not complete list of Teensyduino macros

• ARDUINO_ARCH_AVR - Avr Architecture / (all Teensy < 3.0)
• TEENSYDUINO=Version - Is a Teensy + gives TD version
• KINETISL - Teensy LC 
• KINETISK - All Teensy 3.x
• __MK20DX128__ - Teensy 3.0
• __MK20DX256__ - Teensy 3.1, 3.2
• __MK64FX512__ - Teensy 3.5
• __MK66FX1M0__ - Teensy 3.6
• __IMXRT1062__ - all Teensy 4.x + Teensy 4 MM
• ARDUINO_TEENSY2 - Teensy 2
• ARDUINO_TEENSY30 - Teensy 3.0
• [...]
• ARDUINO_TEENSY40 - Teensy 4.0
• ARDUINO_TEENSY41 - Teensy 4.1
• ARDUINO_TEENSYMM - Teensy 4 MM
• NUM_DIGITAL_PINS
• NUM_ANALOG_INPUTS
• LED_BUILTIN - default 13
• BUILTIN_SDCARD - defined on boards with SD slot
• ARM_DWT_CYCCNT - ARM cycle counter
• [...]  TODO

Audio Library:

• AUDIO_BLOCK_SAMPLES - default 128 (Teensy LC: 64) - Number of samples per audio block.
• AUDIO_SAMPLE_RATE_EXACT - default 44.100f (T4), 44117.64706 (Teensy LC + Teensy 3.x)
• MAX_AUDIO_MEMORY

USB Modes:

• USB_SERIAL
• USB_DUAL_SERIAL
• USB_TRIPLE_SERIAL
• USB_KEYBOARDONLY
• USB_HID
• USB_SERIAL_HID
• USB_TOUCHSCREEN
• USB_HID_TOUCHSCREEN
• USB_MIDI
• USB_MIDI4
• USB_MIDI16
• USB_MIDI_SERIAL
• USB_MIDI4_SERIAL
• USB_MIDI16_SERIAL
• USB_RAWHID
• USB_FLIGHTSIM
• USB_FLIGHTSIM_JOYSTICK
• USB_MTPDISK
• USB_AUDIO
• USB_MIDI_AUDIO_SERIAL
• USB_MIDI_AUDIO_DUAL_SERIAL (non-standard)
• USB_MIDI16_AUDIO_SERIAL
• USB_EVERYTHING